1. Field of the Invention
The present invention relates to a physical information acquisition method, a physical information acquisition device, and a semiconductor device. In more detail, the present invention relates to a signal acquisition technique appropriate for applying to a solid image capturing apparatus and so forth which use a semiconductor device for physical quantity distribution detection which is configured of multiple unit components, having sensitivity as to electromagnetic waves to be input from the outside such as light, radiation, or the like, being arrayed, and can read out a physical quantity distribution converted into an electric signal by the unit components as an electric signal. Particularly, the present invention relates to an arrangement for eliminating influence of unnecessary wavelength (a typical example is infrared light and ultraviolet light as to visible light) region components which filter in a principal wavelength region (a typical example is a visible light region).
2. Description of the Related Art
Physical quantity distribution detecting semiconductor devices, which are configured of a plurality of unit components (e.g., pixels) having sensitivity as to change in physical quantity such as electromagnetic waves to be input from the outside such as light, radiation, or the like being arrayed in a line shape, or in a matrix form, are employed in various fields.
For example, with the visual equipment field, a CCD (Charge Coupled Device) type for detecting change in light serving as one example of physical quantity (one example of electromagnetic waves) or MOS (Metal Oxide Semiconductor), or CMOS (Complementary Metal-oxide Semiconductor) type solid image capturing apparatuses are employed. These read out a physical quantity distribution converted into an electric signal by unit components (pixels in the case of solid image capturing apparatuses) as an electric signal.
For example, a solid state image capturing device detects electromagnetic waves to be input from the outside such as light, radiation, and so forth using a photodiode serving as an photoelectric conversion device (light receiving device; photo sensor) provided in the image capturing unit (pixel unit) of a device unit to generate and accumulate signal electric charge, and reads out the accumulated signal electric charge (photoelectron) as image information.
Also, recently, arrangements for capturing an image using visible light and capturing an image using infrared light have been proposed (e.g., see U.S. Pat. No. 5,965,875, Japanese Unexamined Patent Application Publication No. 2004-103964, Japanese Unexamined Patent Application Publication No. 10-210486, Japanese Unexamined Patent Application Publication No. 2002-369049, Japanese Unexamined Patent Application Publication No. 06-121325, Japanese Unexamined Patent Application Publication No. 09-166493, Japanese Unexamined Patent Application Publication No. 09-130678, Japanese Unexamined Patent Application Publication No. 2000-59798, and Japanese Unexamined Patent Application Publication No. 2003-70009). For example, the position of the emitting light point of infrared rays is prepared beforehand to trace this, whereby the position of the emitting light point of infrared light present within a visible light image can be detected. Also, even in the event of no visible light, e.g., even in the event of night, a brilliant image can be obtained by illuminating infrared light to capture an image. Further, in addition to visible light, infrared light is employed, whereby sensitivity can be improved.
The arrangements described in U.S. Pat. No. 5,965,875, and Japanese Unexamined Patent Application Publication No. 2004-103964 relate to a single-plate type utilizing the difference of absorption coefficients based on wavelengths in the depth direction of a semiconductor.
Also, the arrangements described in Japanese Unexamined Patent Application Publication No. 10-210486, Japanese Unexamined Patent Application Publication No. 2002-369049, and Japanese Unexamined Patent Application Publication No. 06-121325 relate to a multi-plate type for receiving visible light and infrared light at separate image capturing devices using a wavelength resolution optical system such as a wavelength separating mirror or prism or the like as an input optical system.
Also, the arrangement described in Japanese Unexamined Patent Application Publication No. 09-166493 relates to a single-plate type for receiving visible light and infrared light at the same image capturing device using a rotating type wavelength resolution optical system as an input optical system. For example, insertion/extraction of an infrared light cut filter is performed in a rotating-mechanical manner, and when inserting an infrared cut filter, a visible color image which has no influence from near-infrared light and infrared light is output, but when extracting an infrared light cut filter, an image to which the light intensity of visible light and near-infrared light is added is output.
Also, the arrangement described in Japanese Unexamined Patent Application Publication No. 09-130678 relates to a type for receiving visible light and infrared light at the same image capturing device using a diaphragm optical system having a wavelength resolution function as an input optical system.
Also, the arrangement described in Japanese Unexamined Patent Application Publication No. 2000-59798 is an arrangement wherein a color filter for transmitting near-infrared light is disposed on an image capturing device having sensitivity as to near-infrared light and visible light, and also adjustment means are provided for adjusting the position of the infrared cut filter between a position where incident light to the image capturing device passes through the infrared cut filter and a position where incident light to the image capturing device does not pass through the infrared cut filter, and when sharing the infrared cut filter for photographing using near-infrared light and for photographing using visible light, both of the sensitivity as to a near-infrared light region and the sensitivity as to a visible region of the image capturing device are effectively utilized by switching the position of the infrared cut filter.
Also, the arrangement described in Japanese Unexamined Patent Application Publication No. 2003-70009 is an arrangement wherein correction for reducing the value of a color difference signal and/or luminance signal depending on the influence degree of infrared light as to the value of a color difference signal or luminance signal to eliminate the influence of infrared light. As one example, an arrangement is made wherein in the event that color filters are complementary-color filters of magenta, green, cyan, and yellow, correction is performed as to a color difference signal R-Y, and each color output signal of magenta and yellow.